Safety-belt arrangement

ABSTRACT

A web-grabber for use with a safety-belt comprises a housing(5) formed as an extrusion of aluminium. A wedge(13) is located within a central passage(6) within the housing. An additional element(20) is also present within the passage(6) having a first side(21) adapted to abut one of the substantially parallel side walls of the passage(6) and an opposed inclined face(22) along which the wedge(13) may slide. The wedge is adapted to engage wedgingly the webbing(3) of a safety-belt, with a face(14) of the wedge engaging the webbing(3) and pressing it against an opposed element(11) which passes through the passage(6) and which secures the extrusion(5) to a retractor unit(1).

THE PRESENT INVENTION relates to a safety-belt arrangement and moreparticularly to a safety-belt arrangement intended for use in a motorvehicle.

BACKGROUND OF THE INVENTION

It has been proposed previously to provide a safety-belt having aretractor reel adapted to retract the safety-belt when it is not in use.It has also been proposed to provide a web-grabber associated with thesafety-belt. Such a web-grabber comprises a housing surrounding thesafety-belt and incorporating a wedge which can be moved to a positionin which the wedge engages and retains the safety-belt. The wedge may bemoved to the safety-belt retaining position in the event that anaccident should arise, thus helping prevent any of the safety-belt beingpaid out in an unintentional manner.

In prior-proposed web-grabbers a housing is provided which is in theform of a casting of metal or a moulding of plastic. The casting ormoulding defines a passage through which the safety-belt may pass, thepassage having a first planar wall against which the safety-belt mayrun, and a second opposed wall which is inclined in towards the firstwall. A wedge element is mounted for axial sliding movement within thehousing. One face of the wedge element abuts and may run along theinclined wall as the wedge element moves into the safety-belt retainingposition. When in the safety-belt retaining position the wedge elementtraps the safety belt against the said planar wall.

It is relatively expensive to provide a housing in the form of a castingor a moulding.

The present invention seeks to provide an improved safety-beltarrangement.

SUMMARY OF THE INVENTION

According to this invention there is provided a safety-belt arrangementfor use in a motor vehicle comprising a web-grabber, adapted to grab theweb of a safety-belt, the web-grabber comprising a housing formed of anextrusion of metal, the extrusion defining a through-passage havingsubstantially parallel opposed side walls, through which the webbing isadapted to pass, the web-grabber further comprising a wedge presentwithin the through-passage movable from a release position to aweb-grabbing position, and an additional element having a face adaptedto abut one side wall of the passage and another face, inclined thereto,against which the wedge element may slide.

Preferably the extrusion is of aluminium.

Conveniently the extrusion is provided with reinforcing means adapted toreinforce the opposed side walls of the passage.

Advantageously the side wall of the passage abutted by the additionalelement is of serrated profile, the corresponding face of the additionalelement having a corresponding serrated profile.

Conveniently the web-grabber is secured to a retractor for thesafety-belt.

Advantageously the extrusion is secured the retractor by means of astrap having one end in the form of a hook which engages part of theextrusion, a part which passes through the passage defined through thehousing, and a part which is adapted to be secured to an anchoringpoint. The strap can thus be secured to the anchoring point directlyconnecting the extrusion to the anchorning point and transferring anyload applied to the extrusion directly to the anchoring point. Theretractor is mounted on the strap.

In an alternative arrangement a single fastening bolt is used to securethe retractor mechanism to a fixed part of a motor vehicle, and tosecure the strap to the retractor mechanism, the strap having one end inthe form of a hook which engages part of the extrusion.

Conveniently the retractor mechanism is provided with means which, whenactuated, move the wedge to the web-grabbing position in which the wedgeengages the webbing of the safety belt.

Advantageously spring means are provided which normally bias the wedgeto a non-webbing-grabbing position.

Conveniently the additional element comprises side pieces which extendacross the passage, engaging and retaining the strap, and havingprojections which are secured to the retractor.

In an alternative embodiment the additional element carries lugs havingengaging formations therein adapted to engage corresponding formationsformed on the retractor. The engaging formations may be sliding snapformations.

The invention also relates to a method of assembling an arrangement inaccordance with the invention comprising the steps of securing theextrusion to the strap by inter-engaging the hook at one end of thestrap with part of the extrusion, and then engaging the strap with theretractor mechanism.

Preferably, before engaging the strap with the retractor mechanism, theadditional element is connected to the retractor, the additional elementbeing located in the extrusion as the strap is engaged with theretractor mechanism.

Preferably, the additional element is connected to the retractor byinter-engaging formations on lugs associated with the additional elementwith protrusions provided on the retractor.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention may be more readily understood, and so thatfurther features thereof may be appreciated, the invention will now bedescribed, by way of example, with reference to the accompanyingdrawings in which:

FIG. 1 is a side elevational view of a seat-belt arrangement inaccordance with the invention,

FIG. 2 is a partial sectional view of the embodiment of the FIG. 1illustrating certain components thereof,

FIG. 3 is a further partial sectional view illustrating furthercomponents of the arrangement of FIG. 1,

FIG. 4 is a sectional view of an extrusion used to form a housingforming part of the embodiment of FIGS. 1 to 3,

FIG. 5 is an end view of the housing formed from the extrusion of FIG. 4illustrating, in part, a holding element, an additional element, a wedgeand the webbing of a safety-belt.

FIG. 6 is a diagrammatic view of two components of a seat beltarrangement in accordance with the invention prior to assembly, withparts thereof cut away,

FIG. 7 is a perspective view illustrating the two components of FIG. 6when inter-connected.

FIG. 8 is a side view of a further component of a seat belt arrangementin accordance with the invention,

FIG. 9 is a side view of yet another component of a seat beltarrangement in accordance with the invention,

FIG. 10 illustrates the components of FIGS. 8 and 9 wheninter-connected,

FIG. 11 illustrates the assembled components illustrated in FIG. 7 andthe assembled components illustrated in FIG. 10 prior to assembly ofthose components,

FIG. 12 illustrates the components of FIG. 11 when inter-connected, and

FIG. 13 is a perspective view of a modified form of the seat beltarrangement similar to that illustrated in FIG. 12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1 to 3 of the accompanying drawings a safety-beltarrangement is provided comprising a conventional retractor mechanism 1which is associated with a bolt 2 which, in use, affixes the retractor 1to part of the chassis of a motor vehicle. The retractor may be of aconventional design. Associated with the retractor is a safety-belt 3which is adapted to be wound into the retractor when not in use. Theretractor incorporates a mechanism which, should an accident occur,locks a spindle within the retractor to prevent the paying-out of anysafety-belt. Such an arrangement is conventional.

Associated with the retractor 1 is a web-grabber 4. As has beenmentioned above it has been proposed previously to provide aweb-grabber, but the web-grabber of the present invention is of a ratherdifferent design to prior-proposed web-grabbers.

The web-grabber 4 comprises a housing 5 formed from a metal extrusion,such as an extrusion of aluminium or the like.

The extrusion defines a central axially extending passage 6 havingparallel opposed side walls. As can be seen most clearly from FIG. 4 ofthe accompanying drawings, one side wall 7 of the passage 6 issubstantially planar whereas the opposed side wall 8 is serrated.

The extrusion forming the housing 5 may comprise various reinforcingcomponents 9,10 associated with the side walls.

The housing 5 is held in position relative to the retractor 1 by meansof an elongate metal holding element 11 which comprises a metal strap.One end of the elongate holding element 11 has an aperture through whichthe bolt 2 passes, but fixes the retractor mechanism to the chassis of amotor vehicle. The other end of the elongate metal strap 11 passesthrough the central passage 6 defined within the extrusion 5, lyingadjacent the planar side wall 7, the metal strap 11 terminating with ahook-like formation 12 which engages the extrusion 5 to hold theextrusion in position.

A wedge element 13 is provided which is received within the passage 6.The wedge element has a planar face 14 which lies adjacent one side ofthe webbing 3 of the safety-belt which passes through the passage 6. Theother side of the webbing of the safety-belt runs adjacent the metalstrap 11. The planar face 14 is provided with a plurality of teeth 15adapted to engage the webbing of the safety-belt 3.

The side 16 of the wedge opposed to the planar side 14 is inclined at anangle thereto. The wedge is provided with a protruding lug 17 which isconnected by a connector 18 to a mechanism present within the retractor1 adapted to move the wedge, as will be described hereinafter, to anoperative position. A spring element 19 is provided located between theend of the housing 5 and the lug 17 in order to resiliently bias thewedge to a release position as shown in FIG. 2.

Contained within the passage 6 defined within the housing 5 is anadditional element 20 which may be made of metal or which may be made ofa tough plastics material. The additional element 20 has a serrated face21 adapted to abut the serrated side wall 8 of the passage 6. Theadditional element 20 also has an inclined face 22 which abuts andguides the inclined face 16 of the wedge. As can be seen most clearlyfrom FIG. 5 the additional element also has side pieces 23,24 whichextend across the passage 6 within the extrusion 5, these side piecesabutting the sides of the metal strap 11 thus retaining the strap 11firmly in position.

As can be seen from FIG. 5, the wedge 13 is located adjacent theadditional element 20 with the planar face 14 thereof (which carries theteeth 15) separated from the webbing 3 of the safety-belt. Thus, thesafety-belt may readily pass through the web-grabber when the componentsare in the initial position as illustrated. The side pieces 23,24 of theadditional element 20 extend (as can be seen in FIG. 1) towards the mainbody of the retractor 1 and are secured thereto by appropriate fasteningmeans 25,26.

With the arrangement in the condition illustrated, with the edge in the"release" position, the safety-belt may pass freely through theweb-grabber. Should an accident arise, a mechanism within the retractor1 which is responsive to deceleration in excess of a predetermined limitwill cause the lug 17 of the wedge 13 to be moved against the springbias provided by the spring 19, causing the inclined face 16 of thewedge to slide along the inclined face 22 of the additional element 20,bringing the planar face 14 of the wedge, with the teeth 15, intocontact with the webbing 3 of the safety-belt. If the safety-belt thentends to be withdrawn from the retractor mechanism, the wedge is broughtinto a tight clamping condition, with the webbing 3 being clampedtightly between the planar face 14 of the wedge and the strap 11. Theweb grabber 4 thus prevents any further seat bolt being paid out. Anytension or load applied to the seat belt is transferred to the housing5, and then, through the strap 11 to the mounting bolt 2. It isenvisaged that none of the load applied to the seat belt in an accidentwill be transferred to the retractor or the retractor housing.

Referring now to FIGS. 6 to 13 of the accompanying drawings, a slightlymodified embodiment of the invention is illustrated, showing how thevarious components are assembled.

A retractor reel 31 is of substantially conventional design and has twospaced apart forwardly protruding lugs, only one of which, 32, isillustrated, located on either side of an open mouth through which aseat belt 33 emerges. The interior face of each lug 32 is provided withvarious protrusions 34. The retractor reel housing may be made ofplastic material, since the retractor is not involved in the transfer ofload from the seat belt to the structure or chassis of the vehicle whenan accident arises.

A further component 35, is provided comprising two spaced apart lugs,only one of which, 36, is illustrated, the lug 36 having formed, on itsexterior surface, a protruding formation 37. The formations on the lugsprovided on the element 35 are adapted to inter-engage with theprotrusions 34 provided on the lugs on the retractor mechanism 31.

The further component 35, which may made of plastic, carries twoprojecting arms 38, carried by the lugs 36, but off-set inwardlyrelative to the lugs 36. Extending transversely between the arms 38 isan element 39 corresponding to the additional element 20, the element 39having an inclined face and a planar face provided with a plurality ofteeth.

The further component 35 is mounted on the retractor mechanism 31 bysliding the further component 35 upwardly into engagement with theretractor mechanism 31 as generally indicated by the arrow 40. Theprotruding formation 37 provided on the element 39 lockingly engage theprotrusions 34 provided on the lugs of the retractor mechanism 31. Thetwo components, when inter-connected, have the appearance as shown inFIG. 7.

Referring now to FIG. 8, a metal strap 50 is illustrated having ahook-shaped formation 51 at one end thereof. A reinforced aperture 52 isformed at the other end of the strap to receive a bolt to secure thestrap to an anchor point on a vehicle.

FIG. 9 illustrates a housing 60 which may be substantially identicalwith the housing 5 illustrated in FIG. 4.

FIG. 10 illustrates the components of FIGS. 8 and 9 wheninter-connected. The hook-shaped formation 51 provided at one end of thestrap 50 has been inter-engaged with one of the webs forming part of thehousing 60.

FIG. 11 illustrates the assemblies of FIGS. 7 and 10 co-aligned forinter-connection. The assembly comprising the strap 50 in the housing 60is moved toward the left in FIG. 11, with the strap thus being locatedbeneath the main part of the retractor 31. The forwardly extending arms38 provided on the further component 35 mounted on the retractor 31 passinto the axially extending passage present in the housing 60corresponding to the passage 6 described with reference to FIG. 4. Awedge element corresponding directly with the wedge element 13 islocated in position within the passage as the elements areinter-connected, the wedge element having a protruding lug correspondingto the lug 17 which is connected to a connector, corresponding to theconnector 18 and thus to a mechanism present within the retractor 31adapted to move the wedge element to an operative position. A springelement corresponding to the spring element 19 is also provided.

A complete assembly, similar to that illustrated in FIG. 12, isillustrated in perspective in FIG. 13.

It is to be appreciated that the main component of the housing of theweb-grabber is an aluminium extrusion which can be fabricated relativelycheaply, but which may easily have the necessary strength. Because themain element is an extrusion, meaning that any through-passage will havesubstantially parallel opposed walls, the additional element is providedwhich has one wall adapted to abut one of the said parallel walls andanother wall inclined thereto to provide an inclined face along whichthe wedge may move from the release position to the web-grabbingposition.

A preferred embodiment of the invention may be assembled in a relativelystraightforward manner. The strap, such as the strap 12 or the strap 50may very easily be connected to the housing formed of the extrusion ofaluminium to form a sub-component. That sub-component may subsequentlybe connected to the retractor reel and the additional element which, inco-operation with the extruded housing, provides the inclined face alongwhich the wedge may run.

The inter-connection of the additional component which carries theinclined face along which the wedge may run with the rest of theretractor housing can be a relatively simple sliding snap-fitarrangement, as illustrated in the embodiments of FIGS. 6 to 13.

We claim:
 1. A safety-belt arrangement in a motor vehicle having achassis, said safety-belt arrangement comprising a retractor mechanismand a safety-belt having a web and associated with said retractormechanism, said retractor mechanism being provided with means which fixthe retractor mechanism in position on the chassis, and a web-grabberadapted to grab the web of the safety-belt, said web-grabber comprisinga housing formed of an extrusion of metal and defining a through-passagehaving substantially parallel opposed side walls through which said webof the safety-belt passes, said web-grabber further comprising a wedgewithin the through-passage and being movable from a release position toa web-grabbing position, and an additional element having a face adaptedto abut one side wall of the passage and another face, inclined thereto,against which said wedge element may slide, a strap for securing saidhousing to part of the chassis, said strap having one end which engagespart of said housing, an intermediate part which passes through thepassage defined through the housing, and a further part secured to thechassis of the motor vehicle.
 2. An arrangement according to claim 1,wherein the metal is aluminum.
 3. An arrangement according to claim 1,wherein said extrusion is provided with reinforcing means forreinforcing the opposed side walls of the passage.
 4. An arrangementaccording to claim 1, wherein said face of said additional element abutssaid one side wall of the passage, said one side wall having a serratedprofile and the corresponding face of the additional element having acorresponding serrated profile.
 5. An arrangement according to claim 4,wherein said additional element comprises side pieces which extendacross the passage, engaging and retaining said strap, and havingprojections which are secured to said retractor mechanism.
 6. Anarrangement according to claim 4, wherein said additional elementcarries lugs which engage formations formed on said retractor.
 7. Anarrangement according to claim 6, wherein said formations are slidingsnap formations.
 8. A safety-belt arrangement in a motor vehicle havinga chassis, said safety-belt arrangement comprising a retractor mechanismand a safety-belt having a web and being associated with said retractormechanism, said retractor mechanism being provided with means which fixthe retractor mechanism in position on the chassis, and a web-grabber,adapted to grab the web of the safety-belt, said web-grabber comprisinga housing defining a through-passage through which said web of saidsafety-belt passes, said web-grabber further comprising an elementmovable from a release position to a web-grabbing position, a strap forsecuring said housing to part of the chassis, one end of said strapengaging part of said housing, an intermediate part which passes throughthe passage defined through said housing, and a further part secured tothe chassis of the motor vehicle.
 9. An arrangement according to claim8, wherein said one end of said strap is in the form of a hook whichengages part of said housing.
 10. An arrangement according to claim 8,further comprising a single fastening bolt which fixes said retractormechanism to the chassis, said bolt also engaging said further part ofsaid strap.
 11. An arrangement according to claim 1, wherein theretractor mechanism is provided with means which, when actuated, movesaid wedge to the web-grabbing position in which said wedge engages saidweb of the safety belt.
 12. An arrangement according to claim 1, furthercomprising spring means normally biasing said wedge to anon-webbing-grabbing position.
 13. A method of assembling a safety-beltarrangement in a motor vehicle having a chassis, said safety-beltarrangement comprising a retractor mechanism and a safety-belt havingweb and associated with said retractor mechanism, said retractormechanism being provided with means which fix the retractor mechanism inposition on the chassis, land a web-grabber adapted to the web of thesafety-belt, said web-grabber comprising a housing formed of anextrusion of metal and defining a through-passage having substantiallyparallel opposed side walls through which said web of the safety-beltpasses, said web-grabber further comprising a wedge within thethrough-passage and being movable from a release position to aweb-grabbing position, and an additional element having a face adaptedto abut one side wall of the passage and another face, inclined thereto,against which said wedge element may slide, a strap for securing saidhousing to part of the chassis, said strap having one end which engagespart of said housing, an intermediate part which passes through thepassage defined through the housing, and a further part secured to thechassis of the motor vehicle, said method comprising the steps ofsecuring the housing to the strap by interengaging a hook at said oneend of the strap with part of the housing, and then engaging the strapwith the retractor mechanism.
 14. A method according to claim 13,wherein, before the step of engaging, the strap with the retractormechanism, the additional element is connected to the retractormechanism, the additional element being located in the extrusion as thestrap is engaged with the retractor mechanism.
 15. A method according toclaim 14, wherein the additional element is connected to the retractorby interengaging formations on lugs associated with the additionalelement with protrusions provided on the retractor mechanism.